Question: Solve for $q$ : $q - 24 = -20$
Solution: Add $24$ to both sides: $ \begin{eqnarray} \\ q - 24 &=& -20 \\ \\ {+24} && {+24} \end{eqnarray} $ $ \begin{eqnarray} \hphantom{-24 + q} &\hphantom{=}& \hphantom{-20} \\ q &=& -20 {+ 24} \\ \end{eqnarray} $ Simplify. $ q = 4$